Information disk apparatus and information disk apparatus installing direction detection method

ABSTRACT

The direction in which an information disk apparatus is installed is judged without employing a sensor means.  
     A control means ( 116 ) measures the number of track crossings when a reading means ( 104 ) is moved by a driving means ( 109 ) in a direction corresponding to the radius of an optical disk ( 102 ) for a predetermined period of time, and judges a direction in which a DVD-ROM player ( 101 ) is installed on the basis of the measured number of track crossings.

TECHNICAL FIELD

The present invention relates to an information disk apparatus and amethod for detecting a direction in which the information disk apparatusis installed and, more particularly, to an improved method for detectinga direction in which a device for recording or reproducing a signalin/from a disk-shaped information recording medium is installed.

BACKGROUND ART

In recent years, there is a demand that computer devices such as apersonal computer and a game machine have a variety of designs and,accordingly, it is supposed that information disk apparatuses mounted onthese computer devices are installed in various directions.

It is known that the information disk apparatus is required to detect aninstalling direction thereof and change various kinds of controlparameters according to the installing direction, thereby to performhigh-speed recording/reproduction, enhance the accuracy of therecording/reproduction, increase a speed for seeking a targetinformation track or the like.

Accordingly, there is generally adopted a method of preparing firmwarein which an optimum control parameter is previously set for eachinstalling direction, or a method of setting information according tothe installing direction through external jumper setting, switchingmeans or the like, to set an optimum parameter.

Further, according to a method as described in Japanese Published PatentApplication No. Hei. 10-255287, an object lens, a pickup device whichsupports the object lens so that it is movable at least in the trackingdirection, a pickup carrier member for carrying the pickup device, atracking control circuit for driving the object lens in the directionperpendicular to tracks, a traverse control circuit for driving thepickup carrier member in the direction perpendicular to the tracks, aposition detector for detecting the initial posture of the object lenswith respect to the pickup, and a compensation circuit which supplies acompensation signal according to the output from the position detectorto the tracking control circuit and the traverse control circuit areincluded, whereby tracking control and traverse control can be performedin an optimum state at all times, independently of an installed state ofa device.

Further, there is also known a method in which a sensor means thatdetects the direction in which a disk drive is set is provided in adevice, thereby to detect the direction in which the device isinstalled.

However, in the method of preparing firmware in which an optimum controlparameter is previously set for each installing direction, and themethod of setting an installing direction through external jumpersetting, switching means or the like, a user is required to changesetting of the installing direction every time the user changes thedirection in which a computer device is installed. Accordingly, whenerroneous setting is performed, the information disk apparatus fails toachieve its original performance.

Also, in the method disclosed in the Japanese Published PatentApplication No. Hei. 10-255287, since a positional relationship betweenthe object lens and the pickup is detected, an error is easily generateddue to variations in traverse loads, and in a device having a mechanismwith the object lens whose weight is significantly reduced, an amount ofdisplacement of the object lens, which is caused by gravity, is smalland, thus, an accurate installing direction is not always detected.Moreover, in the method employing an installing direction detectionmeans, the sensor means increases the cost of the device and a space forinstalling the sensor means in the device becomes a problem.

The present invention is made to solve the above-described conventionalproblems and has for its object to provide an information disk apparatusand an information disk apparatus installing direction detection method,which enable to accurately detect the installing direction at all timeswithout employing a sensor means and with no increase in the costs.

DISCLOSURE OF THE INVENTION

To solve the above-mentioned problems, according to Claim 1 of thepresent invention, there is provided an information disk apparatus whichrecords or reproduces information in/from an information disk on whichinformation tracks are formed spirally or concentrically comprising: acontrol means for: controlling a driving means so that it reciprocates areading means for reading the information from the drivingly rotatinginformation disk, in a direction corresponding to the radius of theinformation disk, and calculating the number of track crossing timesthat the information tracks are crossed by the locus for thereciprocation, on the basis of the information read by the informationreading means at the reciprocation, and judges a direction in which theinformation disk apparatus is installed on the basis of the calculationresult. Therefore, the installing direction is detected on the basis ofthe number of track crossings when the reading means is moved in theradius direction, whereby no additional sensor, circuit or the like isrequired, and the direction in which the information disk apparatus isinstalled can be accurately detected at all times.

According to Claim 2 of the present invention, in the information diskapparatus as defined in Claim 1, the information disk is an opticaldisk, the information reading means is an optical pickup, and thecontrol means controls the optical pickup to focus on an informationrecording surface of the optical disk at the information reading.Therefore, the installing direction is detected on the basis of thenumber of track crossings when the reading means is moved in the radiusdirection in a focus-on state, whereby no additional sensor, circuit orthe like is required, and the direction in which the information diskapparatus is installed can be accurately detected at all times.

According to Claim 3 of the present invention, in the information diskapparatus as defined in Claim 2, the control means stops a trackingdrive by the optical pickup at the information reading. Therefore, theinstalling direction is detected on the basis of the number of trackcrossings when the reading means is moved in the radius direction in astate where the focus is on and the tracking drive is stopped, wherebyno additional sensor, circuit or the like is required, and the directionin which the information disk apparatus is installed can be accuratelydetected at all times.

According to Claim 4 of the present invention, there is provided aninformation disk apparatus which records or reproduces informationin/from an information disk on which information tracks are formedspirally or concentrically, comprising: a disk rotation means forrotating the information disk; a reading means for reading a signal fromthe information disk; a driving means for driving the reading means in adirection corresponding to the radius of the information disk; a trackcrossing signal generation means for generating an information trackcrossing signal of the information disk from a reproduction signal fromthe reading means; and a control means for controlling the disk rotationmeans, the reading means, the driving means, and the track crossingsignal generation means, in which the control means drives the readingmeans in the direction corresponding to the radius of the informationdisk for a predetermined period of time by means of the driving means,while counting the information track crossing signal generated by thetrack crossing signal generation means, and detects a direction in whichthe information disk apparatus is installed on the basis of the obtainedcount value. Therefore, the installing direction is detected on thebasis of a track crossing count value when the reading means is moved inthe radius direction for a predetermined period of time, whereby noadditional sensor, circuit or the like is required, and the direction inwhich the information disk apparatus is installed can be accuratelydetected at all times.

According to Claim 5 of the present invention, the information diskapparatus as defined in Claim 4, which is able to reproduce or recordinformation from/in plural types of information disks having differenttrack pitches, further comprises: a track pitch detecting means fordetecting a track pitch of the information disk, in which the controlmeans moves the reading means in a direction corresponding to the radiusof the information disk for a predetermined period of time at apredetermined speed, by means of the driving means, while counting theinformation track crossing signal generated by the track crossing signalgeneration means, and detects the direction in which the informationdisk apparatus is installed on the basis of the obtained count value andtrack pitch of the information disk. Therefore, the installing directionis detected on the basis of a track crossing count value when thereading means is moved in the radius direction for a predeterminedperiod of time, whereby no additional sensor, circuit or the like isrequired, and the direction in which the information disk apparatus isset can be accurately detected at all times.

According to Claim 6 of the present invention, the information diskapparatus as defined in Claim 5 further comprises: a table whichindicates standard track pitch values for respective types of theinformation disks, in which the track pitch detection means detects thetype of the information disk, and refers to the table of track pitchvalues, thereby detecting the track pitch of the information disk.Therefore, the installing direction is detected on the basis of a trackcrossing count value when the reading means is moved in the radiusdirection for a predetermined period of time, whereby no additionalsensor, circuit or the like is required, and the direction in which theinformation disk apparatus is installed can be accurately detected atall times.

According to Claim 7 of the present invention, in the information diskapparatus as defined in Claim 5, the track pitch detection means has alinear speed detection means for detecting a linear speed of theinformation disk; and a reproduction speed detection means for detectinga current reproduction speed of the information disk, and detects thetype of the information disk, and the control means detects a linearspeed of the disk by employing the linear speed detection means, rotatesthe information disk which is mounted on the disk rotation means at aprescribed speed, moves the reading means to a position corresponding toa prescribed address on the information disk (hereinafter, referred tosimply as an “address”) by means of the driving means, detects areproduction speed at the prescribed rotational speed and at theprescribed address, by employing the reproduction speed detection means,and calculates the track pitch of the information disk on the basis ofthe linear speed of the information disk which is detected by the linearspeed detection means, the reproduction speed detected at the prescribedrotational speed and address, the prescribed rotational speed, theaddress value, an innermost circumference diameter of a data area whichis inherent in the detected type of the information disk, and a datarate value in a case of reproduction at a prescribed reproduction speedwhich is inherent in the detected type of the information disk.Therefore, the installing direction is detected on the basis of a trackcrossing count value when the reading means is moved in the radiusdirection for a predetermined period of time, whereby no additionalsensor, circuit or the like is required, and the direction in which theinformation disk apparatus is installed can be accurately detected atall times.

According to Claim 8 of the present invention, in the information diskapparatus as defined in Claim 5, the control means compares the obtainedcount value with a threshold value, thereby detecting the direction inwhich the information disk apparatus is installed. Therefore, theinstalling direction is detected on the basis of a track crossing countvalue when the reading means is moved in the radius direction for apredetermined period of time, whereby no additional sensor, circuit orthe like is required, and the direction in which the information diskapparatus is installed can be accurately detected at all times.

According to Claim 9 of the present invention, there is provided aninformation disk apparatus which records or reproduces informationin/from an information disk on which information tracks are formedspirally or concentrically, comprising: a disk rotation means forrotating the information disk; a reading means for reading a signal fromthe information disk; a driving means for driving the reading means in adirection corresponding to the radius of the information disk; a trackcrossing signal generation means for generating a information trackcrossing signal of the information disk from a reproduction signal fromthe reading means; and a control means for controlling the disk rotationmeans, the reading means, the driving means, and the track crossingsignal generation means, in which the control means reciprocates thereading means in the direction corresponding to the radius of theinformation disk for a predetermined period of time by means of thedriving means, while counting the information track crossing signalgenerated by the track crossing signal generation means, and detects adirection in which the information disk apparatus is installed on thebasis of the count values obtained for the reciprocation. Therefore, theinstalling direction is detected on the basis of a track crossing countvalue when the reading means is moved between the inner circumferenceside of the information disk and the outer circumference side for apredetermined period of time, whereby the direction in which theinformation disk apparatus is installed can be accurately detected atall times even when there is a wide range of variations of load on thedriving means.

According to Claim 10 of the present invention, in the information diskapparatus as defined in Claim 9, the direction in which the informationdisk apparatus is installed is detected on the basis of a differencebetween a count value for a forward path and a count value for abackward path in the count values for the reciprocation. Therefore, theinstalling direction is detected on the basis of a track crossing countvalue when the reading means is moved between the inner circumferenceside of the information disk and the outer circumference side for apredetermined period of time, whereby the direction in which theinformation disk apparatus is installed can be accurately detected atall times even when there is a wide range of variations of load on thedriving means.

According to Claim 11 of the present invention, in the information diskapparatus as defined in Claim 9, the direction in which the informationdisk apparatus is installed is detected on the basis of a ratio betweena count value for a forward path and a count value for a backward pathin the count values for the reciprocation. Therefore, the installingdirection is detected on the basis of a track crossing count value whenthe reading means is moved between the inner circumference side of theinformation disk and the outer circumference side for a predeterminedperiod of time, whereby the direction in which the information diskapparatus is installed can be accurately detected at all times even whenthere is a wide range of variations of load on the driving means.

According to Claim 12 of the present invention, the information diskapparatus as defined in Claim 9, which is able to reproduce or recordinformation from/in plural types of information disks having differenttrack pitches, further comprises: a track pitch detecting means fordetecting a track pitch of the information disk, in which the controlmeans reciprocates the reading means in the direction corresponding tothe radius of the information disk for a predetermined period of time bymeans of the driving means, while counting the information trackcrossing signal generated by the track crossing signal generation means,and detects the direction in which the information disk apparatus isinstalled on the basis of the obtained count values for thereciprocation and track pitch of the information disk. Therefore, theinstalling direction is detected on the basis of a track crossing countvalue when the reading means is moved between the inner circumferenceside of the information disk and the outer circumference side for apredetermined period of time, whereby the direction in which theinformation disk apparatus is installed can be accurately detected atall times even when there is a wide range of variations of load on thedriving means.

According to Claim 13 of the present invention, in the information diskapparatus as defined in Claim 9, the control means compares the obtainedcount values for the reciprocation with a threshold value, therebydetecting the direction in which the information disk apparatus isinstalled. Therefore, the installing direction is detected on the basisof a track crossing count value when the reading means is moved betweenthe inner circumference side of the information disk and the outercircumference side for a predetermined period of time, whereby thedirection in which the information disk apparatus is installed can beaccurately detected at all times even when there is a wide range ofvariations of load on the driving means.

According to Claim 14 of the present invention, the information diskapparatus as defined in Claim 4 or 9 further comprises a rotationalspeed detection means for detecting a rotational speed of theinformation disk, in which the time for which the reading means is movedby the driving means is an integer multiple of a time required for onerotation which is detected by the rotational speed detection means.Therefore, the reading means is moved according to a disk rotation cycleso that the reading means is located at the same rotational position atstart and end of the movement, whereby even when there is significanteccentricity between the information disk and the disk rotation means orvibrations, an influence on track crossing due to the eccentricity orvibrations is countervailed, and thus the direction in which theinformation disk apparatus is installed is accurately detected at alltimes.

According to Claim 15 of the present invention, in the information diskapparatus as defined in any of Claims 1, 4, 10, and 11, the drivingmeans is set so that it can be driven with an inclination with respectto the gravity direction in at least one of directions in which theinformation disk apparatus is installed, the reading means isreciprocated by the driving means in the radial direction for apredetermined period of time, from an inner circumference of theinformation disk toward an outer circumference as well as from an outercircumference toward an inner circumference, while the track crossingsignal generated by the track crossing signal generation means iscounted, and the direction in which the information disk apparatus isinstalled is detected on the basis of the obtained count value.Therefore, it is possible to provide an information disk apparatus whichenables to judge a direction in which the reading means is driven as oneof three directions, i.e., upward and downward directions when theinformation disk apparatus is installed vertically and the informationdisk is ejected in the lateral direction, and the horizontal directionwhen the information disk apparatus is installed horizontally.

According to Claim 16 of the present invention, in the information diskapparatus as defined in Claim 15, the inclination with respect to thegravity direction is between 15° and 75° or 105° and 165°. Therefore, itis possible to provide an information disk apparatus which enables tojudge a direction in which the reading means is driven as one of threedirections, i.e., upward and downward directions when the informationdisk apparatus is installed vertically and the information disk isejected in the lateral direction, and the horizontal direction when theinformation disk apparatus is installed horizontally.

According to Claim 17 of the present invention, in the information diskapparatus as defined in Claim 15, the inclination with respect to thegravity direction is not approximately equal to any of 45°, 90°, 135°,and 180°. Therefore, it is possible to provide an information diskapparatus which enables to judge a direction in which the reading meansis driven as one of five directions, i.e., upward and downwarddirections when the information disk apparatus is installed verticallyand the information disk is ejected in the lateral direction, upward anddownward directions when the information disk apparatus is installedvertically and the information disk is ejected in the verticaldirection, and a horizontal direction when the information diskapparatus is installed horizontally.

According to Claim 18 of the present invention, in the information diskapparatus as defined in Claim 15, the inclination with respect to thegravity direction is between 15° and 30°, 60° and 75°, 105° and 120°, or150° and 165°. Therefore, it is possible to provide an information diskapparatus which enables to judge a direction in which the reading meansis driven as one of five directions, i.e., upward and downwarddirections when the information disk apparatus is installed verticallyand the information disk is ejected in the lateral direction, upward anddownward directions when the information disk apparatus is installedvertically and the information disk is ejected in the verticaldirection, and a horizontal direction when the information diskapparatus is installed horizontally.

According to Claim 19 of the present invention, there is provided amethod for detecting a direction in which an information disk apparatusthat records or reproduces information in/from an information disk onwhich information tracks are formed spirally or concentrically isinstalled, comprising: reciprocating a reading means for reading theinformation from the drivingly rotating information disk, in a directioncorresponding to the radius of the information disk; and obtaining thenumber of track crossing times that the information tracks are crossedby the locus for the reciprocation, on the basis of the information readby the reading means at the reciprocation, thereby judging the directionin which the information disk apparatus is installed. Therefore, theinstalling direction is detected on the basis of the number of trackcrossings when the reading means is moved in the radius direction,whereby no additional sensor, circuit or the like is required, and thedirection in which the information disk apparatus is installed can beaccurately detected at all times.

According to Claim 20 of the present invention, in the information diskapparatus installing direction detection method as defined in Claim 19,the information disk is an optical disk, the information reading meansis an optical pickup, and a control means controls the optical pickup tofocus on an information recording surface of the optical disk, at theinformation reading. Therefore, the installing direction is detected onthe basis of the number of track crossings when the reading means ismoved in the radius direction in a focus-on state, whereby no additionalsensor, circuit or the like is required, and the direction in which theinformation disk apparatus is installed can be accurately detected atall times.

According to Claim 21 of the present invention, in the information diskapparatus installing direction detection method as defined in Claim 20,the control means stops a tracking drive by the optical pickup at theinformation reading. Therefore, the installing direction is detected onthe basis of the number of track crossings when the reading means ismoved in the radius direction in a state where the focus is on and thetracking drive is stopped, whereby no additional sensor, circuit or thelike is required, and the direction in which the information diskapparatus is installed can be accurately detected at all times.

According to Claim 22 of the present invention, there is provided amethod for detecting a direction in which an information disk apparatusthat records or reproduces information in/from an information disk onwhich information tracks are formed spirally or concentrically isinstalled, comprising: generating a information track crossing signal ofthe information disk from a reproduction signal which is obtained fromthe information disk by a reading means; moving the reading means by adriving means in a direction corresponding to the radius of theinformation disk, for a predetermined period of time, while counting theinformation track crossing signal; and detecting the direction in whichthe information disk apparatus is installed, on the basis of theobtained count value. Therefore, the installing direction is detected onthe basis of a track crossing count value when the reading means ismoved in the radius direction for a predetermined period of time,whereby no additional sensor, circuit or the like is required, and thedirection in which the information disk apparatus is installed can beaccurately detected at all times.

According to Claim 23 of the present invention, in the information diskapparatus installing direction detection method as defined in Claim 22,the information disk apparatus is able to reproduce or recordinformation from/in plural types of information disks having differenttrack pitches, a track pitch of the information disk is detected by atrack pitch detection means, the reading means is moved by the drivingmeans, in the direction corresponding to the radius of the informationdisk, for a predetermined period of time at a predetermined speed, whilethe information track crossing signal is counted, and the direction inwhich the information disk apparatus is installed is detected on thebasis of the obtained count value and track pitch of the informationdisk. Therefore, the installing direction is detected on the basis of atrack crossing count value when the reading means is moved in the radiusdirection for a predetermined period of time, whereby no additionalsensor, circuit or the like is required, and the direction in which theinformation disk apparatus is installed can be accurately detected atall times.

According to Claim 24 of the present invention, in the information diskapparatus installing direction detection method as defined in Claim 23,a table which indicates track pitch standard values for respective typesof the information disks is provided, and the track pitch detectionmeans detects the type of the information disk, and refers to the tableof the track pitch values, thereby detecting the track pitch of theinformation disk. Therefore, the installing direction is detected on thebasis of a track crossing count value when the reading means is moved inthe radius direction for a predetermined period of time, whereby noadditional sensor, circuit or the like is required, and the direction inwhich the information disk apparatus is installed can be accuratelydetected at all times.

According to Claim 25 of the present invention, in the information diskapparatus installing direction detection method as defined in Claim 23,the track pitch detection means has a linear speed detection means fordetecting a linear speed of the information disk; and a reproductionspeed detection means for detecting a current reproduction speed of theinformation disk, and detects the type of the information disk, thelinear speed detection means detects a linear speed of the disk, theinformation disk mounted on the disk rotation means is rotated at aprescribed speed, the reading means is moved to a position correspondingto a prescribed address on the information disk (hereinafter, referredto simply as an “address”) by the driving means, the reproduction speeddetection means detects a reproduction speed at the prescribedrotational speed and at the prescribed address, and the track pitch ofthe information disk is calculated on the basis of the linear speed ofthe information disk which is detected by the linear speed detectionmeans, the reproduction speed detected at the prescribed rotationalspeed and address, the prescribed rotational speed, the address value,an innermost circumference diameter of a data area which is inherent inthe detected type of the information disk, and a data rate value inreproduction at a prescribed reproduction speed which is inherent in thedetected type of the information disk. Therefore, the installingdirection is detected on the basis of a track crossing count value whenthe reading means is moved in the radius direction for a predeterminedperiod of time, whereby no additional sensor, circuit or the like isrequired, and the direction in which the information disk apparatus isinstalled can be accurately detected at all times.

According to Claim 26 of the present invention, the information diskapparatus as defined in Claim 22 comprises: comparing the obtained countvalue with a threshold value, thereby detecting the direction in whichthe information disk apparatus is installed. Therefore, the installingdirection is detected on the basis of a track crossing count value whenthe reading means is moved in the radius direction for a predeterminedperiod of time, whereby no additional sensor, circuit or the like isrequired, and the direction in which the information disk apparatus isinstalled can be accurately detected at all times.

According to Claim 27 of the present invention, there is provided amethod for detecting a direction in which an information disk apparatusthat records or reproduces information in/from an information disk onwhich information tracks are formed spirally or concentrically,comprising: generating a information track crossing signal of theinformation disk from a reproduction signal which is obtained by areading means from the information disk; reciprocating the reading meansby a driving means in a direction of the radius of the information disk,for a predetermined period of time, while counting the information trackcrossing signal; and detecting the direction in which the informationdisk apparatus is installed, on the basis of the obtained count valuesfor the reciprocation. Therefore, the installing direction is detectedon the basis of a track crossing count value when the reading means ismoved between the inner circumference side of the information disk andthe outer circumference side for a predetermined period of time, wherebythe direction in which the information disk apparatus is installed canbe accurately detected at all times even when there is a wide range ofvariations of load on the driving means.

According to Claim 28 of the present invention, in the information diskapparatus installing direction detection method as defined in Claim 27,the direction in which the information disk apparatus is installed isdetected on the basis of a difference between a count value for aforward path and a count value for a backward path in the count valuesfor the reciprocation. Therefore, the installing direction is detectedon the basis of a track crossing count value when the reading means ismoved between the inner circumference, side of the information disk andthe outer circumference side for a predetermined period of time, wherebythe direction in which the information disk apparatus is installed canbe accurately detected at all times even when there is a wide range ofvariations of load on the driving means.

According to Claim 29 of the present invention, in the information diskapparatus installing direction detection method as defined in Claim 27,the direction in which the information disk apparatus is installed isdetected on the basis of a ratio between a count value for a forwardpath and a count value for a backward path in the count values for thereciprocation. Therefore, the installing direction is detected on thebasis of a track crossing count value when the reading means is movedbetween the inner circumference side of the information disk and theouter circumference side for a predetermined period of time, whereby thedirection in which the information disk apparatus is installed can beaccurately detected at all times even when there is a wide range ofvariations of load on the driving means.

According to Claim 30 of the present invention, in the information diskapparatus installing direction detection method as defined in Claim 27,the information disk apparatus is able to reproduce or recordinformation from/in plural types of information disks having differenttrack pitches, a track pitch of the information disk is detected by atrack pitch detection means, the reading means is reciprocated by thedriving means in the direction corresponding to the radius of theinformation disk, for a predetermined period of time, while theinformation track crossing signal is counted, and the direction in whichthe information disk apparatus is installed is detected on the basis ofthe obtained count values for the reciprocation and track pitch of theinformation disk. Therefore, the installing direction is detected on thebasis of a track crossing count value when the reading means is movedbetween the inner circumference side of the information disk and theouter circumference side for a predetermined period of time, whereby thedirection in which the information disk apparatus is installed can beaccurately detected at all times even when there is a wide range ofvariations of load on the driving means.

According to Claim 31 of the present invention, the information diskapparatus installing direction detection method as defined in Claim 27comprises: comparing the obtained count values for the reciprocationwith a threshold value, thereby detecting the direction in which theinformation disk apparatus is installed. Therefore, the installingdirection is detected on the basis of a track crossing count value whenthe reading means is moved between the inner circumference side of theinformation disk and the outer circumference side for a predeterminedperiod of time, whereby the direction in which the information diskapparatus is installed can be accurately detected at all times even whenthere is a wide range of variations of load on the driving means.

According to Claim 32 of the present invention, in the information diskapparatus installing direction detection method as defined in Claim 22or 27, the information disk apparatus further comprises a rotationalspeed detection means for detecting a rotational speed of theinformation disk, and the time for which the reading means is moved bythe driving means is an integer multiple of a time required for onerotation which is detected by the rotational speed detection means.Therefore, the reading means is moved according to a disk rotation cycleso that the reading means is located at the same rotational position atstart and end of the movement, whereby even when there is significanteccentricity between the information disk and the disk rotation means orvibrations, an influence on track crossing due to the eccentricity orvibrations is countervailed, and thus the direction in which theinformation disk apparatus is installed is accurately detected at alltimes.

According to Claim 33 of the present invention, in the information diskapparatus installing direction detection method as defined in any ofClaim 19, 22, 28, and 29, the driving means is installed so that it canbe driven with an inclination with respect to the gravity direction inat least one of directions in which the information disk apparatus isinstalled. Therefore, it is possible to provide an information diskapparatus installing direction detection method by which a direction inwhich the reading means is driven can be judged as one of threedirections, i.e., upward and downward directions when the informationdisk apparatus is installed vertically and the information disk isejected in the lateral direction, and a horizontal direction when theinformation disk apparatus is installed horizontally.

According to Claim 34 of the present invention, in the information diskapparatus installing direction detection method as defined in Claim 33,the inclination with respect to the gravity direction is between 15° and75° or 105° and 165°. Therefore, it is possible to provide aninformation disk apparatus installing direction detection method bywhich a direction in which the reading means is driven can be judged asone of three directions, i.e., upward and downward directions when theinformation disk apparatus is installed vertically and the informationdisk is ejected in the lateral direction, and a horizontal directionwhen the information disk apparatus is installed horizontally.

According to Claim 35 of the present invention, in the information diskapparatus installing direction detection method as defined in Claim 33,the inclination with respect to the gravity direction is notapproximately equal to any of 45°, 90°, 135°, and 180°. Therefore, it ispossible to provide an information disk apparatus installing directiondetection method by which a direction in which the reading means isdriven can be judged as one of five directions, i.e., upward anddownward directions when the information disk apparatus is installedvertically and the information disk is ejected in the lateral direction,upward and downward directions when the information disk apparatus isinstalled vertically and the information disk is ejected in the verticaldirection, and a horizontal direction when the information diskapparatus is installed horizontally.

According to Claim 36 of the present invention, in the information diskapparatus installing direction detection method as defined in Claim 33,the inclination with respect to the gravity direction in the informationdisk device between 15° and 30°, 60° and 75°, 105° and 120°, or 150° and165°. Therefore, it is possible to provide an information disk apparatusinstalling direction detection method by which a direction in which thereading means is driven can be judged as one of five directions, i.e.,upward and downward directions when the information disk apparatus isinstalled vertically and the information disk is ejected in the lateraldirection, upward and downward directions when the information diskapparatus is installed vertically and the information disk is ejected inthe vertical direction, and a horizontal direction when the informationdisk apparatus is installed horizontally.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram illustrating a construction of a DVD-ROMplayer as an example of an information disk apparatus according to firstand second embodiments of the present invention.

FIG. 2 is a flowchart illustrating an example of an operation of acontrol means in the information disk apparatus according to the firstembodiment of the invention.

FIG. 3 is a flowchart illustrating an example of an operation of acontrol means in the information disk apparatus according to the secondembodiment of the invention.

FIG. 4 is a block diagram illustrating a construction of a DVD-ROMplayer as an example of an information disk apparatus according to athird embodiment of the present invention.

FIG. 5 is a flowchart illustrating an example of an operation of acontrol means in the information disk apparatus according to the thirdembodiment of the invention, as an example.

FIG. 6 is a flowchart illustrating an example of an operation of thecontrol means in the information disk apparatus according to the thirdembodiment of the invention.

FIG. 7 is a diagram illustrating a driving direction when an informationdisk apparatus according to a fourth embodiment of the present inventionis horizontally installed.

FIG. 8 is a diagram illustrating a driving direction when theinformation disk apparatus according to the fourth embodiment of theinvention is installed so that a disk is ejected in the upwarddirection.

FIG. 9 is a diagram illustrating a driving direction when an informationdisk apparatus according to a fifth embodiment of the present inventionis installed vertically so that a disk is ejected in the lateraldirection.

FIG. 10 is a diagram illustrating another driving direction when theinformation disk apparatus according to the fifth embodiment of theinvention is installed vertically so that the disk is ejected in thelateral direction.

BEST MODE TO EXECUTE THE INVENTION EMBODIMENT 1

A first embodiment corresponds to the invention described in Claims 1 to8 and 19 to 26. According to the first embodiment, the number of trackcrossings is measured when a reading means is driven in a directioncorresponding to the radius of a disk mounted on an information diskapparatus, for a predetermined period of time, and the direction inwhich the information disk apparatus is installed is judged on the basisof this measured value, whereby the direction in which the informationdisk apparatus is installed is judged without employing a sensor means.

Hereinafter, the first embodiment according to the present inventionwill be described with reference to FIG. 1.

FIG. 1 is a block diagram when the present invention is applied to aDVD-ROM player.

In FIG. 1, a DVD-ROM player (information disk apparatus) 101 is able toplay back various types of optical disks, in addition to a primaryDVD-ROM, as optical disks (information disks) 102.

The DVD-ROM player shown in this first embodiment is able to play backdisks such as CD-ROMs (CD-ROM, CD-R, and CD-RW), DVD-ROMs (DVD-5, DVD-9,and DVD-R4.7G), and DVD-R3.9Gs. Standard track pitches of the respectivedisks are as follows.

CD-ROM 1.6 μm

DVD-ROM 0.74 μm

DVD-R3.9G 0.80 μm.

Numeral 103 denotes a disk rotation means for rotating the optical disk102 which is mounted on the DVD-ROM player 101, at a prescribed speed.Numeral 104 denotes a reading means for reading a data signal from theoptical disk 102. In the DVD-ROM player, for example, the reading means104 is constituted by an element 105 which emits two lasers withdifferent oscillation wavelengths for CD-ROMs and DVD-ROMS, an objectlens 106 for condensing the laser beams, and a light detecting element107 of two systems for CD-ROMs and DVD-ROMS. Numeral 108 denotes aconversion means which amplifies the output from the light detectingelement 107, selects an output signal from the light detecting elementaccording to the type of the optical disk, generates a tracking error(TE), a focus error (FE), a reproduction signal (RF), an ALL Sum signal(AS), an RF envelope signal (RFENV) and the like, and outputs thosesignals, thereby converting the reproduction signal of the optical disk102 into digital data.

Numeral 109 denotes a driving means for moving the reading means 104 ina direction corresponding to the radius of the optical disk 102. Thedriving means 109 comprises, for example, two means: a traverse drivingmeans 110 for driving the entire reading means 104 in the direction ofthe radius of the optical disk, and a tracking actuator 111 for drivingthe object lens 106 provided in the reading means 104 in the radialdirection to finally drive the object lens 106 in the radial directionof the optical disk 102. Numeral 112 denotes a track crossing signalgeneration means which generates an information track crossing signal onthe basis of a reproduction signal when a laser beam emitted from thereading means 104 crosses tracks which are formed on the optical disk.The information track crossing signal is generated by a method forbinarizing a tracking error signal outputted from the reading means 104with a hysteresis comparator or a comparator, by a method for comparingphases of the binarized signal and a not-on-track signal which isgenerated from an envelope of the RF signal with each other, to detectthe movement direction, or the like.

Numeral 113 denotes a track pitch detection means for detecting a trackpitch of the information disk. As a method for detecting the trackpitch, there is a method, for example, in which the type of theinformation disk is judged, and a standard value of the track pitchcorresponding to the judged disk type is used as a detection value.

Usually, since the DVD-ROM player 101 is able to play back data fromvarious types of information disks as described above, and requiresdifferent light sources and detection signal generation methodsaccording to the types of the disk, the DVD-ROM player 101 initiallyjudges the type of the mounted disk by various kinds of methods. Thejudgement is made as follows. A judgement is made as to whether the diskis a disk of ROM type (CD-ROM, CD-R, DVD-ROM, or DVD-R) or a re-writabletype disk (CD-RW) from the reflectance of the information disk, on thebasis of the amplitude of a focus error signal at focus search, byemploying, for example, a laser for CDs, and a judgement is further madeas to whether the disk is a DVD type disk or a CD type disk from adegree of modulation of the RF signal, to select a required light sourceand signal path. Finally, it is checked whether TOC (TOP OF CONTENTS)data can be read from the information disk or not, and whether theselected disk type is correct or not from the TOC information. Then, astandard value of a track pitch corresponding to the disk type isselected.

As another method for calculating the track pitch, there is a method inwhich a linear speed detection means for detecting a linear speed of theoptical disk 102 and a playback speed detection means for detecting thecurrent playback speed of the optical disk 102 are provided in the trackpitch detection means 113, the type of the optical disk 102 is detected,the linear speed of the disk is detected by employing the linear speeddetection means, the information disk mounted on the disk rotation means103 is rotated at a prescribed speed, the reading means 104 is moved toa position corresponding to a prescribed address (hereinafter, referredto simply as an “address”) by driving the driving means 109, and aplayback speed at the prescribed rotational speed and at the prescribedaddress is detected by employing the playback speed detection means,thereby calculating a track pitch of the information disk from thelinear speed of the optical disk which is detected by the linear speeddetection means, the playback speed detected at the prescribedrotational speed and address, the prescribed rotational speed, theaddress value, the innermost circumference diameter in a data areainherent in the detected disk type, and a data rate value when theplayback is carried out at a prescribed reproduction speed inherent inthe disk type. Numeral 116 denotes a control means which receivessignals from the conversion means 108 and the track crossing signalgeneration means 112 to process those signals, as well as controls thedisk rotation means 103, the reading means 104, the conversion means108, and the driving means 109.

Next, the operation of the control means 116 detecting the direction inwhich the DVD-ROM player 101 is installed will be described withreference to a flowchart in FIG. 2.

At startup of the DVD-ROM player 101, the drive control means 116controls the disk rotation means 103, whereby the optical disk 102 isrotated (step S101 in FIG. 2). Then, the control means 116 drives thedriving means 109 in the direction of the radius of the optical disk 102for a predetermined period of time with predetermined output, i.e., at apredetermined speed (step S102), so as to move the reading means 104,and counts the number of track crossings, which is the number of timesthat tracks are intersected at right angles by the locus of the drivingmeans 109, on the basis of the output signal from the track crossingsignal generation means 112 while the driving means 109 is driven (stepS103). A distance for which the reading means 104 is moved can becalculated by multiplying the number of track crossings by a measurementvalue of the track pitch detection means 113 (step S104). Naturally, thesame effect is also obtained even when the number of track crossings ismultiplied by a ratio of the measurement value to a track pitch of astandard disk, or a value proportional to that ratio.

Next, the control means 116 compares the obtained movement distance witha prepared threshold value, thereby judging the direction in which theDVD-ROM player 101 is installed (step S105). There are three directionsthat can be judged as direction in which the driving means 109 ismovable: the horizontal direction in the case of horizontalinstallation, i.e., when the information disk apparatus is installedhorizontally, and the upward and downward directions when theinformation disk apparatus is installed vertically. In the case ofvertical installation, the device is not necessarily required to beinstalled in the accurately vertical direction, and the detection can besimilarly performed even when the device is installed in the directionssomewhat inclined from the accurately vertical direction.

A method for deciding the threshold value is as follows. The directionin which the driving mans 109 is movable is previously set horizontalwith respect to the gravity direction, and the above-described movementdistance is measured. Then, a threshold value for the measured movementdistance is decided with taking into consideration a change in themovement distance due to gravitational acceleration, the coefficient offriction of the driving means 109 and variations thereof, and the like,when the direction in which the driving means 109 is movable is setperpendicular to the gravity direction.

When the above-mentioned movement distance in cases where the directionin which the driving means 109 is movable is horizontal is within apredetermined range, it is judged that the information disk apparatus isinstalled in the horizontal direction. In cases where the reading meansis moved from the outer circumference of the disk toward the innercircumference, when the movement distance is smaller than thepredetermined range, it is judged that the information disk apparatus isinstalled so that the inner circumference direction of the disk isupward. On the other hand, when the movement distance is larger than thepredetermined range, it is judged that the information disk apparatus isinstalled so that the inner circumference direction of the disk isdownward. Further, it is also possible to detect an approximate angle ofinclination of the driving means 109 with respect to the gravitydirection, on the basis of the movement distance.

As described above, according to the first embodiment, a distance forwhich the reading means is moved is calculated on the basis of thenumber of track crossings and the track pitch of the disk, and thecalculated movement distance is compared with a threshold value, wherebythe installing direction is detected merely by arithmetic operations.Therefore, three installing directions, that is, the horizontaldirection when the information disk apparatus is installed horizontally,and the upward and downward directions when the information diskapparatus is installed vertically, can be detected without requiring asensor so that problems of cost increases due to provision of thesensor, or a space for setting the sensor do not occur.

While in the first embodiment the movement distance is calculated on thebasis of the number of track crossings and the track pitch of the disk,and the calculated movement distance is compared with a threshold value,it is also possible that only the number of track crossings is employedand a threshold value is prepared for each type of the disk.

Further, while in the first embodiment the driving means 109 is moved inthe radial direction for a predetermined period of time withpredetermined output, while the number of track crossing is counted froman output signal from the track crossing signal generation means 112, atime until the predetermined number of track crossings may be counted.

Furthermore, in the first embodiment the DVD-ROM player is employed asan information disk apparatus, while a DVD-RAM drive, a DVD-R drive, aDVD-RW drive, a DVD+R drive, a DVD+RW drive, a CD-R drive, a CD-RWdrive, and further a writable information disk apparatus such as a harddisk drive are also available.

As described above, according to the first embodiment, the direction inwhich the information disk apparatus is installed is detected on thebasis of the track crossing count value when the reading means is movedin the radial direction for a predetermined period of time, whereby noadditional sensor, circuit or the like is required, and the direction inwhich the information disk apparatus is installed is accurately detectedat all times.

EMBODIMENT 2

A second embodiment corresponds to the invention described in Claims 9to 13 and 27 to 31. According to the second embodiment, the number oftrack crossings is measured when a reading means is reciprocated in theradial direction of an information disk apparatus, from the innercircumference toward the outer circumference as well as from the outercircumference toward the inner circumference, for a predetermined periodof time, and the direction in which the information disk apparatus isinstalled is judged on the basis of the measured track crossing value,whereby the direction in which the information disk apparatus isinstalled is judged without employing a sensor means.

Hereinafter, the second embodiment according to the present inventionwill be described with reference to FIG. 1.

FIG. 1 is a block diagram when the present invention is applied to aDVD-ROM player.

Descriptions of the same or corresponding constituents in FIG. 1 asthose described for the first embodiment will be omitted to avoidduplication.

Next, the operation of the control means 116 detecting the direction inwhich the DVD-ROM player 101 is installed will be described withreference to a flowchart in FIG. 3.

The control means 116 controls the disk rotation means 103, whereby theoptical disk 102 is rotated (step S101 in FIG. 3). Then, the controlmeans 116 drives the driving means 109 in the direction corresponding tothe radius of the optical disk 102 for a predetermined period of timewith predetermined output, i.e., at a predetermined speed (step S106),so as to move the reading means 104 from the inner circumference towardthe outer circumference and, then, from the outer circumference towardthe inner circumference. Then, the control means 116 counts the numberof track crossings from the output signal of the track crossing signalgeneration means 112, with respect to each direction, during thereciprocation (step S103). A distance for which the reading means 104 ismoved is calculated by multiplying the number of track crossings by ameasurement value of the track pitch detection means 113 (step S104).Naturally, the same effect is obtained even when the number of trackcrossings is multiplied by a ratio of the measurement value to a trackpitch of a standard disk, or a value proportional to that ratio. Then,the respective movement distances obtained for the reciprocation arecompared with each other, whereby the direction in which the DVD-ROMplayer is installed is judged (step S107). As a method for thejudgement, there is a method in which a difference between therespective movement distances of the reciprocation is obtained tocompare the obtained difference with a prepared threshold value, amethod in which a ratio between the respective movement distances of thereciprocation is obtained to compare the obtained ratio with a preparedthreshold value, or the like.

While in the second embodiment the movement distance is calculated onthe basis of the number of track crossings and the track pitch of thedisk, and the calculated movement distance is compared with a thresholdvalue, it is also possible that only the number of track crossings isemployed and a threshold value is prepared for each type of the disk.Specifically, when a ratio between the respective movement distances ofthe reciprocation is compared with a threshold value, there is no needof preparing a threshold value for each type of the disk even when thetrack pitch is not employed, because the track pitch is independent of adetected value.

Further, in the second embodiment the driving means 109 is reciprocatedin the radial direction for a predetermined period of time withpredetermined output, and the number of track crossings is counted froman output signal of the track crossing signal generation means 112during the reciprocation, while the number of track crossings can bealso counted by reciprocally measuring a time until the predeterminednumber of track crossings is counted to compare these measured valueswith each other.

Furthermore, in the second embodiment the DVD-ROM player is employed asan information disk apparatus, while a DVD-RAM drive, a DVD-R drive, aDVD-RW drive, a DVD+R drive, a DVD+RW drive, a CD-R drive, a CD-RWdrive, and further a writable information disk apparatus such as a harddisk drive are also available.

As described above, according to the second embodiment, the direction inwhich the information disk apparatus is installed is detected on thebasis of the track crossing count value when the reading means is movedfrom the inner circumference of the information disk toward the outercircumference as well as from the outer circumference toward the innercircumference for a predetermined period of time with predeterminedoutput, whereby the direction in which the information disk apparatus isinstalled is accurately detected at all times even when there is a widerange of variations of loads on the driving means.

EMBODIMENT 3

A third embodiment corresponds to the invention described in Claims 14and 32. According to the third embodiment, a reading means is drivenaccording to a disk rotation cycle so that the reading means is locatedat the same rotational position at start and end of the movement,whereby the direction in which an information disk apparatus isinstalled is accurately detected at all times even when there issignificant eccentricity between an information disk and a disk rotationmeans or vibrations.

Hereinafter, the third embodiment according to the present inventionwill be described with reference to FIG. 4.

FIG. 4 is a block diagram when the present invention is applied to aDVD-ROM player.

Descriptions of the same or corresponding constituents in FIG. 4 asthose described for the first embodiment will be omitted to avoidduplication.

In FIG. 4, numeral 201 denotes a rotational speed detection means. Therotational speed detection means 201 detects a rotational speed of adisk on the basis of disk rotation information which is outputted fromthe disk rotation means 103. For example, when a brushless motor whichis provided with a hall element as a rotation sensor is used as the diskrotation means, an output signal from the hall element is the diskrotation information. When the motor comprises three poles, six pulsesare outputted per rotation, so that the rotational speed detection meansdetects the present disk rotational speed on the basis of these pulses.

Next, the operation of the control means 116 detecting the direction inwhich the DVD-ROM player 101 is installed will be described withreference to a flowchart in FIG. 5.

The control means 116 controls the disk rotation means 103, whereby theoptical disk 102 is rotated (step S101 in FIG. 5). Then, the controlmeans 116 drives the driving means 109 in the radial direction for apredetermined period of time with predetermined output, i.e., at apredetermined speed (step S108), while counting the number of trackcrossings on the basis of the output signal from the track crossingsignal generation means 112 while the driving means 109 is driven (stepS103). At this time, it is assumed that the time for driving the drivingmeans in the radial direction is an integer multiple of the timerequired for one rotation of the disk at the rotational speed detectedby the rotational speed detection means. Therefore, even when there iseccentricity or vibrations on the disk, the rotational positions on thedisk at start and end of measurement of the number of track crossingsare in accord, whereby influences on track crossing due to theeccentricity or vibrations can be eliminated. Next, a movement distancecan be calculated by multiplying the number of track crossings by ameasurement value of the track pitch detection means 113 (step S104).Naturally, the same effect is obtained even when the number of trackcrossings is multiplied by a ratio of the measurement value to a trackpitch of a standard disk, or a value proportional to that ratio.

Thereafter, the direction in which the DVD-ROM player is installed isjudged in a like manner as described for the first or second embodiment(step S105 in FIG. 5).

While in the above description the driving means 109 is driven in thedirection of the radius of the optical disk 102 for a predeterminedperiod of time with predetermined output, i.e., at a predeterminedspeed, as described for the first embodiment, the driving means may bereciprocated as shown in the flowchart in FIG. 6. In the flowchart inFIG. 6, step S109 is a step of reciprocating the driving means in thedirection of the radius of the information disk with predeterminedoutput for a time corresponding to an integer multiple of the timerequired for one rotation of the disk, and step S107 is a step ofcomparing respective movement distances of the reciprocation with eachother to judge the direction in which the DVD-ROM player is installed.

Further, while in the third embodiment the time required for onerotation of the disk is obtained on the basis of the disk rotationalspeed, the same effect can be similarly obtained by setting a drivingtime so that the disk rotational positions at start and end of themeasurement are in accord.

As described above, according to the third embodiment, the reading meansis driven according to a cycle of disk rotation so that it is located atthe same rotation position at start and end of the driving, whereby,even when there is significant eccentricity between the information diskand the disk rotation means or vibrations, an influence on the trackcrossing due to the eccentricity or vibrations is countervailed, andtherefore the direction in which the information disk apparatus isinstalled is accurately detected at all times.

While also in the third embodiment the movement distance is calculatedon the basis of the number of track crossings and the track pitch of thedisk to compare the calculated movement distance with a threshold value,it is also possible that only the number of track crossings is employedand a threshold value is prepared for each type of the disk.

Further, while also in the third embodiment the driving means 109 isdriven in the radial direction for a predetermined period of time withpredetermined output, and the number of track crossings is counted onthe basis of an output signal from the track crossing signal generationmeans 112 while the driving means is driven, the same effect can besimilarly obtained by measuring a time until the predetermined number oftrack crossings is counted.

Furthermore, also in the third embodiment the DVD-ROM player is employedas an information disk apparatus, while a DVD-RAM drive, a DVD-R drive,a DVD-RW drive, a DVD+R drive, a DVD+RW drive, a CD-R drive, a CD-RWdrive, and further a writable information disk apparatus such as a harddisk drive are also available.

EMBODIMENT 4

A fourth embodiment corresponds to the invention described in Claims 15,16, 33, and 34. According to the fourth embodiment, a reading meanswhich is installed in an information disk apparatus to be inclined withrespect to the gravity direction is driven by a driving means in thedirection of the radius of an information disk, whereby the direction inwhich the information disk apparatus is installed is detected.

Hereinafter, the fourth embodiment will be described with reference toFIGS. 7, 9, and 10.

FIG. 1 is a block diagram when the present invention is applied to aDVD-ROM player.

Descriptions the constituents in FIG. 1 that operate in like manners asthose described for the first embodiment will be omitted of to avoidduplication.

FIG. 7 is a diagram illustrating a driving direction Tr1 when theinformation disk apparatus according to the present invention isinstalled horizontally. In the drawing, the driving means 109 is drivenin the direction perpendicular (90°) to the gravity direction G.

FIG. 9 is a diagram illustrating a first driving direction for thedriving means when the information disk apparatus is installedvertically and the disk ejection direction E is a lateral direction. Inthe drawing, the driving means 109 is driven diagonally downward withrespect to the gravity direction G.

FIG. 10 is a diagram illustrating a second driving direction for thedriving means when the information disk apparatus is installedvertically so that the disk ejection direction E is a horizontaldirection. In the drawing, the driving means 109 is driven diagonallyupward with respect to the gravity direction.

Next, the operation of the control means 116 detecting the direction inwhich the DVD-ROM player 101 is installed will be described. The controlmeans 116 controls the disk rotation means 103 to rotate the opticaldisk 102. Then, the control means 116 reciprocates the driving means 109in the radial direction for a predetermined period of time withpredetermined output, and counts the number of track crossings withrespect to each direction, on the basis of the output signal from thetrack crossing signal generation means 112. At this time, the drivingmeans 109 is not driven in the tracking direction Tr2. A distance forwhich the driving means 109 is moved is calculated by multiplying thenumber of track crossings by a measurement value of the track pitchdetection means 113. Naturally, the same effect is obtained even whenthe number of track crossings is multiplied by a ratio of themeasurement value to a track pitch of a standard disk, or a valueproportional to that ratio. Further, the same effect can be achievedsimply by the comparison of the number of track crossings. In the caseof horizontal installation as shown in FIG. 3, the gravity scarcelyaffects the driving means 109 and only friction occurs, whereby thenumbers of track crossings are almost equal for the to and fro movement.

On the other hand, when the driving means 109 is driven diagonallydownward with respect to the gravity direction G as shown in FIG. 9, thegravity affects the driving means in the forward direction in caseswhere tracks are crossed from the inner circumference toward the outercircumference, and in the opposite direction in cases where the tracksare crossed from the outer circumference toward the inner circumference,so that the number of track crossings is larger in the cases where thetracks are crossed from the inner circumference toward the outercircumference.

When the driving means 109 is driven diagonally upward with respect tothe gravity direction G as shown in FIG. 10, the number of trackcrossings is larger on the contrary in cases where the tracks arecrossed from the outer circumference toward the inner circumference.Therefore, the direction in which the DVD-ROM player is installed can bejudged on the basis of a difference or ratio between the numbers oftrack crossings.

It is preferable that the inclination of the driving means 109 to thegravity direction is 15°˜750 or 105°˜165°. In most cases, a typicalinformation disk apparatus is allowed to be installed with aninclination of approximately 0°˜15° in a forward or backward, orrightward or leftward direction with respect to the normal installingdirection, while even when the information disk apparatus is installedwith some inclination, the same effect can be obtained when the angle ofthe inclination is set to an appropriate value within theabove-described ranges.

As described above, according to the fourth embodiment, the readingmeans is reciprocated by the driving means in the direction of theradius of the information disk, and the direction in which theinformation disk apparatus is installed is judged on the basis of adifference between the numbers of track crossings detected during thereciprocation, whereby three installing directions can be judged withoutproviding an additional sensor or the like. The three installingdirections as directions in which the reading means is moved are upwardand downward directions when the information disk apparatus is installedvertically and the information disk is ejected in the lateral direction,and the horizontal direction when the information disk apparatus isinstalled horizontally.

While in the fourth embodiment the driving means 109 is installed sothat the direction in which the driving means 109 is driven is inclinedwith respect to the disk ejection direction, the same effect is achievedwhen the driving means 109 is installed so that the direction in whichthe driving means 109 is driven is inclined with respect to the gravitydirection in the respective installing directions.

EMBODIMENT 5

A fifth embodiment corresponds to the invention described in Claims 17,18, 35, and 36. According to the fifth embodiment, a whole informationdisk apparatus which is installed so that a reading means is installed,being inclined with respect to the gravity direction, can detect adirection in which the information disk apparatus is installed with aninclination within the allowable range, by driving the reading means inthe direction of the radius of an information disk by means of a drivingmeans.

Hereinafter, the fifth embodiment will be described with reference toFIGS. 7, 8, 9, and 10.

FIG. 1 is a block diagram when the present invention is applied to aDVD-ROM player.

Descriptions of the constituents in FIG. 1 that operate in like mannersas those described for the first embodiment will be omitted to avoidduplication.

FIG. 7 is a diagram illustrating the direction in which the drivingmeans is driven when the information disk apparatus is installedhorizontally. In the drawing, the driving means 109 is driven in thedirection perpendicular (90°) to the gravity direction G.

FIG. 8 is a diagram illustrating the driving direction when theinformation disk apparatus is installed vertically so that the diskejection direction E is an upward direction. In the drawing, the drivingmeans 109 is installed with an inclination of approximately 30° to thedisk ejection direction E, and is driven with an inclination ofapproximately 30° with respect to the gravity direction G in theinstalling direction in FIG. 8.

FIG. 9 is a diagram illustrating a first driving direction when theinformation disk apparatus is installed vertically so that the diskejection direction E is a lateral direction. In the drawing, the drivingmeans 109 is driven with an inclination of approximately 120° withrespect to the gravity direction G.

FIG. 10 is a diagram illustrating a second driving direction when theinformation disk apparatus is installed vertically so that the diskejection direction E is a lateral direction. In the drawing, the drivingmeans 109 is driven with an inclination of approximately 60° withrespect to the gravity direction G.

Next, the operation of the control means 116 detecting the direction inwhich the DVD-ROM player 101 is installed will be described. The controlmeans 116 controls the disk rotation means 103 to rotate the opticaldisk 102. Then, the control means 116 reciprocates the driving means 109in the radial direction for a predetermined period of time withpredetermined output, and counts the number of track crossings on thebasis of the output signal from the track crossing signal generationmeans 112, with respect to each direction. A movement distance iscalculated by multiplying the number of track crossings by a measurementvalue of the track pitch detection means 113. Naturally, the same effectis obtained even when the number of track crossings is multiplied by aratio of the measurement value to a track pitch of a standard disk, or avalue proportional to that ratio. Further, the same effect can beachieved simply by the comparison of the number of track crossings. Inthe case of horizontal installation as shown in FIG. 3, the gravityscarcely affects the driving means 109 and only friction included by thedriving means 109 has influences, whereby the numbers of track crossingsare almost equal for the to and fro movement.

On the other hand, when the information disk apparatus is installed sothat the disk ejection direction E is an upper direction, and thedriving means is driven with an inclination of approximately 30° withrespect to the gravity direction G, as shown in FIG. 8, an influence ofgravitational acceleration “g” exerted on the driving means 109 isobtained as follows.a=g*cos ψ  (1),andsince ψ=30° (“*” indicates multiplication),a1=0.8666*g  (2).

+86% of the gravitational acceleration “g” is applied in the directionfrom the outer circumference toward the inner circumference, and −86% ofgravitational acceleration “g” is applied in the direction from theinner circumference toward the outer circumference, respectively.

In the first case where the information disk apparatus is installedvertically so that the disk ejection direction E is a lateral directionas shown in FIG. 9, when the driving means 109 is driven with aninclination of approximately 120° with respect to the gravity direction,an influence of the gravitational acceleration “g” exerted on thedriving means 109 is obtained as follows. Assumed that ψ=120° in theexpression (1),a2=−0.5*g  (3)so that

−50% of the gravitational acceleration “g” is applied in the directionfrom the outer circumference toward the inner circumference, and +50% ofgravitational acceleration “g” is applied in the direction from theinner circumference toward the outer circumference, respectively.

In the second case where the information disk apparatus is installedvertically so that the disk ejection direction E is an upper directionas shown in FIG. 10, when the driving means 109 is driven with aninclination of approximately 60° with respect to the gravity direction,an influence of the gravitational acceleration “g” exerted on thedriving means 109 is obtained as follows. Assumed that ψ=60° in theexpression (1),a3=0.5*g  (4)so that+50% of the gravitational acceleration “g” is applied in the directionfrom the outer circumference toward the inner circumference, and −50% ofgravitational acceleration “g” is applied in the direction from theinner circumference toward the outer circumference, respectively.

Accordingly, there occurs a difference between the numbers of trackcrossings when the driving means 109 is driven in the direction from theouter circumference toward the inner circumference and the number oftrack crossings in the direction from the inner circumference toward theouter circumference. Thus, by comparing the both numbers of trackcrossings, the following four installing directions can be judged.

That is, i) the horizontal installation when the both numbers of trackcrossings are almost equal to each other,

ii) the first vertical installation, i.e., the information diskapparatus is installed vertically so that the disk is ejected in thelateral direction and the driving means is driven diagonally downward,when the number of track crossings from the inner circumference towardthe outer circumference is larger, and

iii) when the number of track crossings from the outer circumferencetoward the inner circumference is larger, from a ratio between thenumbers of track crossings from the outer circumference toward the innercircumference and from the inner circumference toward the outercircumference, {circle around (1)} the second vertical installation,i.e., the information disk apparatus is installed vertically so that thedisk is ejected in the lateral direction and the driving means is drivendiagonally upward, or {circle around (2)} the information disk apparatusis installed vertically so that the disk is ejected in the upwarddirection. It is judged that the information disk apparatus is installedin either one of these states.

While in the fifth embodiment the driving means 109 is installed with aninclination of approximately 30° with respect to the disk ejectiondirection, the same effect can be achieved when the inclination withrespect to the gravity direction is not approximately equal to any of45°, 90°, 135°, and 180°. These angles 45°, 90°, 135°, and 180° areangels which do not cause a difference between the numbers of trackcrossings due to reciprocation and, thus, make it impossible to judgethe installing direction.

In most cases, a typical information disk apparatus is allowed to beinstalled with the inclination of approximately 0°˜15° with respect tothe normal installing direction in the forward or backward, andrightward or leftward directions, while the same effect can be obtainedby setting an angle of the inclination θ with respect to the gravitydirection within one of the ranges 15°˜30°, 60°˜75°, 105°˜120°, or150°˜165° even when the apparatus is installed with some inclination.

In this case, the expression (1) indicating the influence of thegravitational acceleration “g” exerted on the driving means 109 has tobe changed as follows.a=g*(cos ψ)*(cos θ)  (5)

As described above, according to the fifth embodiment, the reading meansis reciprocated by the driving means in the direction of the radius ofthe information disk, and the direction in which the information diskapparatus is installed is judged on the basis of a difference betweenthe numbers of track crossings detected during the reciprocation,thereby detecting the direction in which the information disk apparatusis installed, in which apparatus the reading means is installed beinginclined with respect to the gravity direction, and the wholeinformation disk apparatus is installed with an inclination within theallowable range, without providing an additional sensor or the like.

In the fifth embodiment, the installing direction is selected from thefour kinds of directions, i.e., the horizontal direction, the directionin which the information disk apparatus is installed vertically and thedisk is ejected in the upward direction, the direction in which theinformation disk apparatus is installed vertically and the disk isejected in the lateral direction as well as the driving means is drivendiagonally upward, and the direction in which the information diskapparatus is installed vertically and the disk is ejected in the lateraldirection as well as the driving means is driven diagonally downward.However, it is also possible to add a case where the disk is ejected inthe downward direction.

While in the fifth embodiment the apparatus is installed so that thedirection in which the driving means 109 is driven is inclined withrespect to the disk ejection direction, the same effect is achieved whenthe driving means 109 is installed so that the direction in which thedriving means 109 is driven is inclined with respect to the gravitydirection in the respective installing directions.

APPLICABILITY IN INDUSTRY

As described above, according to an information disk apparatus and aninformation disk apparatus installing direction detection method of thepresent invention, a reading means is driven in the direction of theradius of an information disk, the number of track crossings isdetected, and the direction in which the information disk apparatus isinstalled is judged on the basis of the detected number of trackcrossings. Thereby, it is possible to realize an information diskapparatus and an information disk apparatus installing directiondetection method, that enable judgement of the installing directionwithout a cost increase caused by providing a sensor means and withoutrequiring a place for setting the sensor means.

1-3. (canceled)
 4. An information disk apparatus which records orreproduces information in/from an information disk on which informationtracks are formed spirally or concentrically, comprising: a diskrotation means for rotating the information disk; a reading means forreading a signal from the information disk; a driving means for drivingthe reading means in a direction corresponding to the radius of theinformation disk; a track crossing signal generation means forgenerating an information track crossing signal of the information diskfrom a reproduction signal from the reading means; and a control meansfor controlling the disk rotation means, the reading means, the drivingmeans, and the track crossing signal generation means, wherein thecontrol means drives the reading means in the direction corresponding tothe radius of the information disk for a predetermined period of time bymeans of the driving means, while counting the information trackcrossing signal generated by the track crossing signal generation means,and detects a direction in which the information disk apparatus isinstalled on the basis of the obtained count value.
 5. The informationdisk apparatus as defined in claim 4, which is able to reproduce orrecord information from/in plural types of information disks havingdifferent track pitches, further comprising: a track pitch detectingmeans for detecting a track pitch of the information disk, wherein thecontrol means moves the reading means in a direction corresponding tothe radius of the information disk for a predetermined period of time ata predetermined speed, by means of the driving means, while counting theinformation track crossing signal generated by the track crossing signalgeneration means, and detects the direction in which the informationdisk apparatus is installed on the basis of the obtained count value andtrack pitch of the information disk.
 6. The information disk apparatusas defined in claim 5 further comprising: a table which indicatesstandard track pitch values for respective types of the informationdisks, wherein the track pitch detection means detects the type of theinformation disk, and refers to the table of track pitch values, therebydetecting the track pitch of the information disk.
 7. The informationdisk apparatus as defined in claim 5, wherein the track pitch detectionmeans has a linear speed detection means for detecting a linear speed ofthe information disk; and a reproduction speed detection means fordetecting a current reproduction speed of the information disk, anddetects the type of the information disk, and the control means detectsa linear speed of the disk by employing the linear speed detectionmeans, rotates the information disk which is mounted on the diskrotation means at a prescribed speed, moves the reading means to aposition corresponding to a prescribed address on the information disk(hereinafter, referred to simply as an “address”) by means of thedriving means, detects a reproduction speed at the prescribed rotationalspeed and at the prescribed address, by employing the reproduction speeddetection means, and calculates the track pitch of the information diskon the basis of the linear speed of the information disk which isdetected by the linear speed detection means, the reproduction speeddetected at the prescribed rotational speed and address, the prescribedrotational speed, the address value, an innermost circumference diameterof a data area which is inherent in the detected type of the informationdisk, and a data rate value in a case of reproduction at a prescribedreproduction speed which is inherent in the detected type of theinformation disk.
 8. The information disk apparatus as defined in claim5, wherein the control means compares the obtained count value with athreshold value, thereby detecting the direction in which theinformation disk apparatus is installed.
 9. An information diskapparatus which records or reproduces information in/from an informationdisk on which information tracks are formed spirally or concentrically,comprising: a disk rotation means for rotating the information disk; areading means for reading a signal from the information disk; a drivingmeans for driving the reading means in a direction corresponding to theradius of the information disk; a track crossing signal generation meansfor generating a information track crossing signal of the informationdisk from a reproduction signal from the reading means; and a controlmeans for controlling the disk rotation means, the reading means, thedriving means, and the track crossing signal generation means, whereinthe control means reciprocates the reading means in the directioncorresponding to the radius of the information disk for a predeterminedperiod of time by means of the driving means, while counting theinformation track crossing signal generated by the track crossing signalgeneration means, and detects a direction in which the information diskapparatus is installed on the basis of the count values obtained for thereciprocation.
 10. The information disk apparatus as defined in claim 9,wherein the direction in which the information disk apparatus isinstalled is detected on the basis of a difference between a count valuefor a forward path and a count value for a backward path in the countvalues for the reciprocation.
 11. The information disk apparatus asdefined in claim 9, wherein the direction in which the information diskapparatus is installed is detected on the basis of a ratio between acount value for a forward path and a count value for a backward path inthe count values for the reciprocation.
 12. The information diskapparatus as defined in claim 9, which is able to reproduce or recordinformation from/in plural types of information disks having differenttrack pitches, further comprising: a track pitch detecting means fordetecting a track pitch of the information disk, wherein the controlmeans reciprocates the reading means in the direction corresponding tothe radius of the information disk for a predetermined period of time bymeans of the driving means, while counting the information trackcrossing signal generated by the track crossing signal generation means,and detects the direction in which the information disk apparatus isinstalled on the basis of the obtained count values for thereciprocation and track pitch of the information disk.
 13. Theinformation disk apparatus as defined in claim 9, wherein the controlmeans compares the obtained count values for the reciprocation with athreshold value, thereby detecting the direction in which theinformation disk apparatus is installed.
 14. The information diskapparatus as defined in claim 4 further comprising a rotational speeddetection means for detecting a rotational speed of the informationdisk, wherein the time for which the reading means is moved by thedriving means is an integer multiple of a time required for one rotationwhich is detected by the rotational speed detection means.
 15. Theinformation disk apparatus as defined in claim 4, wherein the drivingmeans is set so that it can be driven with an inclination with respectto the gravity direction in at least one of directions in which theinformation disk apparatus is installed, the reading means isreciprocated by the driving means in the radial direction for apredetermined period of time, from an inner circumference of theinformation disk toward an outer circumference as well as from an outercircumference toward an inner circumference, while the track crossingsignal generated by the track crossing signal generation means iscounted, and the direction in which the information disk apparatus isinstalled is detected on the basis of the obtained count value.
 16. Theinformation disk apparatus as defined in claim 15, wherein theinclination with respect to the gravity direction is between 15° and 75°or 105° and 165°.
 17. The information disk apparatus as defined in claim15, wherein the inclination with respect to the gravity direction is notapproximately equal to any of 45°, 90°, 135°, and 180°.
 18. Theinformation disk apparatus as defined in claim 15, wherein theinclination with respect to the gravity direction is between 15° and30°, 60° and 75°, 105° and 120°, or 150° and 165°. 19-21. (canceled) 22.A method for detecting a direction in which an information diskapparatus that records or reproduces information in/from an informationdisk on which information tracks are formed spirally or concentricallyis installed, comprising: generating an information track crossingsignal of the information disk from a reproduction signal which isobtained from the information disk by a reading means; moving thereading means by a driving means in a direction corresponding to theradius of the information disk, for a predetermined period of time,while counting the information track crossing signal; and detecting thedirection in which the information disk apparatus is installed, on thebasis of the obtained count value.
 23. The information disk apparatusinstalling direction detection method as defined in claim 22, whereinthe information disk apparatus is able to reproduce or recordinformation from/in plural types of information disks having differenttrack pitches, a track pitch of the information disk is detected by atrack pitch detection means, the reading means is moved by the drivingmeans, in the direction corresponding to the radius of the informationdisk, for a predetermined period of time at a predetermined speed, whilethe information track crossing signal is counted, and the direction inwhich the information disk apparatus is installed is detected on thebasis of the obtained count value and track pitch of the informationdisk.
 24. The information disk apparatus installing direction detectionmethod as defined in claim 23, wherein a table which indicates trackpitch standard values for respective types of the information disks isprovided, and the track pitch detection means detects the type of theinformation disk, and refers to the table of the track pitch values,thereby detecting the track pitch of the information disk.
 25. Theinformation disk apparatus installing direction detection method asdefined in claim 23, wherein the track pitch detection means has alinear speed detection means for detecting a linear speed of theinformation disk; and a reproduction speed detection means for detectinga current reproduction speed of the information disk, and detects thetype of the information disk, the linear speed detection means detects alinear speed of the disk, the information disk mounted on the diskrotation means is rotated at a prescribed speed, the reading means ismoved to a position corresponding to a prescribed address on theinformation disk (hereinafter, referred to simply as an “address”) bythe driving means, the reproduction speed detection means detects areproduction speed at the prescribed rotational speed and at theprescribed address, and the track pitch of the information disk iscalculated on the basis of the linear speed of the information diskwhich is detected by the linear speed detection means, the reproductionspeed detected at the prescribed rotational speed and address, theprescribed rotational speed, the address value, an innermostcircumference diameter of a data area which is inherent in the detectedtype of the information disk, and a data rate value in reproduction at aprescribed reproduction speed which is inherent in the detected type ofthe information disk.
 26. The information disk apparatus as defined inclaim 22 comprising: comparing the obtained count value with a thresholdvalue, thereby detecting the direction in which the information diskapparatus is installed.
 27. A method for detecting a direction in whichan information disk apparatus that records or reproduces informationin/from an information disk on which information tracks are formedspirally or concentrically, comprising: generating an information trackcrossing signal of the information disk from a reproduction signal whichis obtained by a reading means from the information disk; reciprocatingthe reading means by a driving means in a direction of the radius of theinformation disk, for a predetermined period of time, while counting theinformation track crossing signal; and detecting the direction in whichthe information disk apparatus is installed, on the basis of theobtained count values for the reciprocation.
 28. The information diskapparatus installing direction detection method as defined in claim 27,wherein the direction in which the information disk apparatus isinstalled is detected on the basis of a difference between a count valuefor a forward path and a count value for a backward path in the countvalues for the reciprocation.
 29. The information disk apparatusinstalling direction detection method as defined in claim 27, whereinthe direction in which the information disk apparatus is installed isdetected on the basis of a ratio between a count value for a forwardpath and a count value for a backward path in the count values for thereciprocation.
 30. The information disk apparatus installing directiondetection method as defined in claim 27, wherein the information diskapparatus is able to reproduce or record information from/in pluraltypes of information disks having different track pitches, a track pitchof the information disk is detected by a track pitch detection means,the reading means is reciprocated by the driving means in the directioncorresponding to the radius of the information disk, for a predeterminedperiod of time, while the information track crossing signal is counted,and the direction in which the information disk apparatus is installedis detected on the basis of the obtained count values for thereciprocation and track pitch of the information disk.
 31. Theinformation disk apparatus installing direction detection method asdefined in claim 27 comprising: comparing the obtained count values forthe reciprocation with a threshold value, thereby detecting thedirection in which the information disk apparatus is installed.
 32. Theinformation disk apparatus installing direction detection method asdefined in claim 22, wherein the information disk apparatus furthercomprises a rotational speed detection means for detecting a rotationalspeed of the information disk, and the time for which the reading meansis moved by the driving means is an integer multiple of a time requiredfor one rotation which is detected by the rotational speed detectionmeans.
 33. The information disk apparatus installing direction detectionmethod as defined in claim 22, wherein the driving means is installed sothat it can be driven with an inclination with respect to the gravitydirection in at least one of directions in which the information diskapparatus is installed.
 34. The information disk apparatus installingdirection detection method as defined in claim 33, wherein theinclination with respect to the gravity direction is between 15° and 75°or 105° and 165°.
 35. The information disk apparatus installingdirection detection method as defined in claim 33, wherein theinclination with respect to the gravity direction is not approximatelyequal to any of 45°, 90°, 135°, and 180°.
 36. The information diskapparatus installing direction detection method as defined in claim 33,wherein the inclination with respect to the gravity direction in theinformation disk device between 15° and 30°, 60° and 75°, 105° and 120°,or 150° and 165°.
 37. The information disk apparatus as defined in claim10, wherein the driving means is set so that it can be driven with aninclination with respect to the gravity direction in at least one ofdirections in which the information disk apparatus is installed, thereading means is reciprocated by the driving means in the radialdirection for a predetermined period of time, from an innercircumference of the information disk toward an outer circumference aswell as from an outer circumference toward an inner circumference, whilethe track crossing signal generated by the track crossing signalgeneration means is counted, and the direction in which the informationdisk apparatus is installed is detected on the basis of the obtainedcount value.
 38. The information disk apparatus as defined in claim 11,wherein the driving means is set so that it can be driven with aninclination with respect to the gravity direction in at least one ofdirections in which the information disk apparatus is installed, thereading means is reciprocated by the driving means in the radialdirection for a predetermined period of time, from an innercircumference of the information disk toward an outer circumference aswell as from an outer circumference toward an inner circumference, whilethe track crossing signal generated by the track crossing signalgeneration means is counted, and the direction in which the informationdisk apparatus is installed is detected on the basis of the obtainedcount value.
 39. The information disk apparatus installing directiondetection method as defined in claim 27, wherein the information diskapparatus further comprises a rotational speed detection means fordetecting a rotational speed of the information disk, and the time forwhich the reading means is moved by the driving means is an integermultiple of a time required for one rotation which is detected by therotational speed detection means.
 40. The information disk apparatusinstalling direction detection method as defined in claim 28, whereinthe driving means is installed so that it can be driven with aninclination with respect to the gravity direction in at least one ofdirections in which the information disk apparatus is installed.
 41. Theinformation disk apparatus installing direction detection method asdefined in claim 29, wherein the driving means is installed so that itcan be driven with an inclination with respect to the gravity directionin at least one of directions in which the information disk apparatus isinstalled.
 42. The information disk apparatus as defined in claim 9,further comprising a rotational speed detection means for detecting arotational speed of the information disk, wherein the time for which thereading means is moved by the driving means is an integer multiple of atime required for one rotation which is detected by the rotational speeddetection means.